Userland: Add pmap utility

2 files changed, 133 insertions, 0 deletions

diff --git a/Base/usr/share/man/man1/pmap.md b/Base/usr/share/man/man1/pmap.md
new file mode 100644
index 0000000000..c1d2eacf36
--- /dev/null
+++ b/Base/usr/share/man/man1/pmap.md
@@ -0,0 +1,27 @@
+## Name
+
+pmap - print memory map of a process
+
+## Synopsis
+
+```**sh
+$ pmap [-x] PID
+```
+
+## Description
+
+Print the memory map of a specified process.
+
+## Options
+
+* `-x`: Extended output
+
+## Examples
+
+```sh
+$ pmap $$
+```
+
+## See also
+
+* [`ps`(1)](../man1/ps.md)
diff --git a/Userland/pmap.cpp b/Userland/pmap.cpp
new file mode 100644
index 0000000000..a0cdf12b72
--- /dev/null
+++ b/Userland/pmap.cpp
@@ -0,0 +1,106 @@
+/*
+ * Copyright (c) 2020, the SerenityOS developers.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <AK/ByteBuffer.h>
+#include <AK/JsonObject.h>
+#include <AK/String.h>
+#include <LibCore/ArgsParser.h>
+#include <LibCore/File.h>
+#include <stdio.h>
+
+int main(int argc, char** argv)
+{
+    if (pledge("stdio rpath", nullptr) < 0) {
+        perror("pledge");
+        return 1;
+    }
+
+    if (unveil("/proc", "r") < 0) {
+        perror("unveil");
+        return 1;
+    }
+
+    unveil(nullptr, nullptr);
+
+    const char* pid;
+    static bool extended = false;
+
+    Core::ArgsParser args_parser;
+    args_parser.add_option(extended, "Extended output", nullptr, 'x');
+    args_parser.add_positional_argument(pid, "PID", "PID", Core::ArgsParser::Required::Yes);
+    args_parser.parse(argc, argv);
+
+    auto file = Core::File::construct(String::format("/proc/%s/vm", pid));
+    if (!file->open(Core::IODevice::ReadOnly)) {
+        fprintf(stderr, "Error: %s\n", file->error_string());
+        return 1;
+    }
+
+    printf("%s:\n", pid);
+
+    if (extended) {
+        printf("Address   Size       Resident   Dirty      Access  VMObject Type          Purgeable  CoW Pages    Name\n");
+    } else {
+        printf("Address   Size       Access  Name\n");
+    }
+
+    auto file_contents = file->read_all();
+    auto json = JsonValue::from_string(file_contents);
+    ASSERT(json.has_value());
+    json.value().as_array().for_each([](auto& value) {
+        auto map = value.as_object();
+        auto address = map.get("address").to_int();
+        auto size = map.get("size").to_string();
+
+        auto readable = map.get("readable").to_bool();
+        auto writable = map.get("writable").to_bool();
+        auto executable = map.get("executable").to_bool();
+        auto access = String::format("%s%s%s", (readable ? "r" : "-"), (writable ? "w" : "-"), (executable ? "x" : "-"));
+
+        printf("%08x  ", address);
+        printf("%-10s ", size.characters());
+        if (extended) {
+            auto resident = map.get("amount_resident").to_string();
+            auto dirty = map.get("amount_dirty").to_string();
+            auto vmobject = map.get("vmobject").to_string();
+            auto purgeable = map.get("purgeable").to_string();
+            auto cow_pages = map.get("cow_pages").to_string();
+            printf("%-10s ", resident.characters());
+            printf("%-10s ", dirty.characters());
+            printf("%-6s  ", access.characters());
+            printf("%-22s ", vmobject.characters());
+            printf("%-10s ", purgeable.characters());
+            printf("%-12s ", cow_pages.characters());
+        } else {
+            printf("%-6s  ", access.characters());
+        }
+        auto name = map.get("name").to_string();
+        printf("%-20s ", name.characters());
+        printf("\n");
+    });
+
+    return 0;
+}